<template>
  <div class="pdf-preview">
    <div class="pdf-header">
      <div class="page-tool">
        <div class="page-tool-item" @click="lastPage">上一页</div>
        <div class="page-tool-item" @click="nextPage">下一页</div>
        <div class="page-tool-item">{{state.pageNum}}/{{state.numPages}}</div>
        <div class="page-tool-item" @click="pageZoomOut">放大</div>
        <div class="page-tool-item" @click="pageZoomIn">缩小</div>
      </div>
    </div>
    <div class="pdf-wrap">
      <vue-pdf-embed :source="state.source" :style="scale" :page="state.pageNum"  class="vue-pdf-embed"  />
    </div>
  </div>
</template>
<script setup>
import { reactive, onMounted, computed } from "vue";
import VuePdfEmbed from "vue-pdf-embed";
import { createLoadingTask } from "vue3-pdfjs/esm"; // 获得总页数

const props = defineProps({
  pdfUrl: {
    type: String,
    required: true
  }
})

const state = reactive({
  source: props.pdfUrl, //预览pdf文件地址
  pageNum: 1, //当前页面
  scale: 1, // 缩放比例
  numPages: 0, // 总页数
});
onMounted(() => {
  const loadingTask = createLoadingTask(state.source);
  loadingTask.promise.then((pdf) => {
    state.numPages = pdf.numPages;
  });
});

const scale = computed(() => `transform:scale(${state.scale});transform-origin:top;`)
function lastPage() {
  if (state.pageNum > 1) {
    state.pageNum -= 1;
  }
}
function nextPage() {
  if (state.pageNum < state.numPages) {
    state.pageNum += 1;
  }
}
function pageZoomOut() {
  if (state.scale < 2) {
    state.scale += 0.1;
  }
}
function pageZoomIn() {
  if (state.scale > 1) {
    state.scale -= 0.1;
  }
}
</script>
<style lang="css" scoped>
.pdf-header{
  z-index: 1;
  position: fixed;
  left: 50%;
  top: 0;
  transform: translate(-50%,0%);
}
.pdf-preview {
  position: relative;
  height: 100vh;
  padding: 20px 0;
  box-sizing: border-box;
  background: rgb(66, 66, 66);
}
.vue-pdf-embed {
  text-align: center;
  width: 1000px;
  border: 1px solid #e5e5e5;
  margin: 0 auto;
  box-sizing: border-box;
}
.pdf-preview {
  position: relative;
  height: 100vh;
  padding: 20px 0;
  box-sizing: border-box;
  background-color: rgb(82, 86, 89);
}
.pdf-wrap{
  margin-top: 60px;
  overflow-y:auto ;
  background-color: rgb(82, 86, 89);
}
.vue-pdf-embed {
  text-align: center;
  width: 1000px;
  border: 1px solid #e5e5e5;
  margin: 0 auto;
  box-sizing: border-box;
}

.page-tool {
  width: 100vw;
  height: 60px;
  background: #333333;
  display: flex;
  justify-content: center;
  align-items: center;
  /*position: absolute;*/
  /*bottom: 35px;*/
  /*padding-left: 15px;*/
  /*padding-right: 15px;*/
  /*display: flex;*/
  /*align-items: center;*/
  /*background: rgb(66, 66, 66);*/
  /*color: white;*/
  /*border-radius: 19px;*/
  /*z-index: 100;*/
  /*cursor: pointer;*/
  /*margin-left: 50%;*/
  /*transform: translateX(-50%);*/
}
.page-tool-item {
  color: white;
  padding: 8px 15px;
  padding-left: 10px;
  cursor: pointer;
}
</style>
